A Dynamized Power Flow Method based on Differential Transformation

As a kind of low-frequency vehicle interior noise, tire acoustic cavity resonance noise plays an important role, since the other noise (e.g., engine noise, wind noise and friction noise) has been largely suppressed. For the suspension system, wheels stand first in the propagation path of this energy. Therefore, it is of great significance to study the influence of wheel design on the transmission characteristics of this vibration energy. However, currently the related research has not received enough attention. In this paper, two sizes of aluminum alloy wheel finite element models are constructed, and their modal characteristics are analyzed and verified by experimental tests simultaneously. A mathematically fitting sound pressure load model arising from the tire acoustic cavity resonance acting on the rim is first put forward. Then, the power flow method is applied to investigate the resonance energy distribution and transmission characteristics in the wheels. The structure intensity distribution and energy transmission efficiency can be described and analyzed clearly. Furthermore, the effects of material structure damping and the wheel spoke number on the energy transmission are also discussed.

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Accurate and Efficient Derivative-Free Three-Phase Power Flow Method for Unbalanced Distribution Networks

Computation ◽

10.3390/computation9060061 ◽

2021 ◽

Vol 9 (6) ◽

pp. 61

Author(s):

Oscar Danilo Montoya ◽

Juan S. Giraldo ◽

Luis Fernando Grisales-Noreña ◽

Harold R. Chamorro ◽

Lazaro Alvarado-Barrios

Keyword(s):

Power Flow ◽

Triangular Matrix ◽

Distribution Networks ◽

Flow Method ◽

Processing Times ◽

Three Phase ◽

Derivative Free ◽

Upper Triangular Matrix ◽

Power Flow Problem ◽

Power Flow Method

The power flow problem in three-phase unbalanced distribution networks is addressed in this research using a derivative-free numerical method based on the upper-triangular matrix. The upper-triangular matrix is obtained from the topological connection among nodes of the network (i.e., through a graph-based method). The main advantage of the proposed three-phase power flow method is the possibility of working with single-, two-, and three-phase loads, including Δ- and Y-connections. The Banach fixed-point theorem for loads with Y-connection helps ensure the convergence of the upper-triangular power flow method based an impedance-like equivalent matrix. Numerical results in three-phase systems with 8, 25, and 37 nodes demonstrate the effectiveness and computational efficiency of the proposed three-phase power flow formulation compared to the classical three-phase backward/forward method and the implementation of the power flow problem in the DigSILENT software. Comparisons with the backward/forward method demonstrate that the proposed approach is 47.01%, 47.98%, and 36.96% faster in terms of processing times by employing the same number of iterations as when evaluated in the 8-, 25-, and 37-bus systems, respectively. An application of the Chu-Beasley genetic algorithm using a leader–follower optimization approach is applied to the phase-balancing problem utilizing the proposed power flow in the follower stage. Numerical results present optimal solutions with processing times lower than 5 s, which confirms its applicability in large-scale optimization problems employing embedding master–slave optimization structures.

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Study of Alternative Schemes for the Parameterization Step of the Continuation Power Flow Method Based on Physical Parameters, Part II: Performance Evaluation

Electric Power Components and Systems ◽

10.1080/15325000390248792 ◽

2003 ◽

Vol 31 (12) ◽

pp. 1167-1177 ◽

Cited By ~ 2

Author(s):

DILSON ALVES ◽

LUIZ CARLOS DA SILVA

Keyword(s):

Performance Evaluation ◽

Power Flow ◽

Physical Parameters ◽

Continuation Power Flow ◽

Flow Method ◽

Power Flow Method

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Efficient three-phase power-flow method for unbalanced radial distribution systems

Melecon 2010 - 2010 15th IEEE Mediterranean Electrotechnical Conference ◽

10.1109/melcon.2010.5476323 ◽

2010 ◽

Cited By ~ 9

Author(s):

Karar Mahmoud ◽

Mamdouh Abdel-Akher

Keyword(s):

Radial Distribution ◽

Power Flow ◽

Distribution Systems ◽

Flow Method ◽

Three Phase ◽

Power Flow Method

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Decoupled AC/DC Power Flow Strategy for Multiterminal HVDC Systems

International Journal of Emerging Electric Power Systems ◽

10.1515/ijeeps-2017-0171 ◽

2018 ◽

Vol 19 (1) ◽

Cited By ~ 2

Author(s):

Yixiang Gao ◽

Shuhui Li ◽

Weizhen Dong ◽

Bing Lu

Keyword(s):

Power Flow ◽

Control Mode ◽

Power Flow Calculation ◽

Flow Calculation ◽

Power System Control ◽

Flow Method ◽

Hvdc System ◽

Dc Power ◽

Bus System ◽

Power Flow Method

AbstractThis paper proposes a decoupled AC/DC power flow approach for multi-terminal HVDC systems. The proposed method simplifies the power flow computation of multi-terminal HVDC systems while accurately reflecting the operation and control characteristics of VSC (voltage source converter) stations in a HVDC network. In the DC network, the power flow calculation is conducted based on a slack DC bus VSC station and power commends issued to other VSC stations from the power system control center. Then, in the AC power flow calculation, VSC stations are treated as special AC generators that can generate and absorb power from the AC grid in active and reactive power or active power and bus voltage control mode. For validation purpose, the conventional unified power flow method for multi-terminal HVDC systems is built. The paper compares the proposed method with the unified power flow method for an 8-bus multi-terminal HVDC system based on MATPOWER. Then, more case studies for different VSC control modes are conducted and evaluated for the 8-bus system. Afterwards, the proposed method is applied to the power flow study of a more practical and complicated multi-terminal HVDC system based on the IEEE 118-bus system.

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A Power Flow Method for Power Distribution Systems Based on a Sinusoidal Transformation to a Convex Quadratic Form

10.1109/pesgm46819.2021.9637963 ◽

2021 ◽

Author(s):

Jaber Valinejad ◽

Lamine Mili ◽

Yijun Xu

Keyword(s):

Quadratic Form ◽

Power Distribution ◽

Power Flow ◽

Distribution Systems ◽

Power Distribution Systems ◽

Flow Method ◽

Power Flow Method

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Efficient Reduction in the Annual Investment Costs in AC Distribution Networks via Optimal Integration of Solar PV Sources Using the Newton Metaheuristic Algorithm

Applied Sciences ◽

10.3390/app112311525 ◽

2021 ◽

Vol 11 (23) ◽

pp. 11525

Author(s):

Oscar Danilo Montoya ◽

Luis Fernando Grisales-Noreña ◽

Lázaro Alvarado-Barrios ◽

Andres Arias-Londoño ◽

Cesar Álvarez-Arroyo

Keyword(s):

Power Flow ◽

Fitness Function ◽

Solution Space ◽

Distribution Networks ◽

Optimal Placement ◽

Mixed Integer ◽

Optimization Approach ◽

Solar Pv ◽

Flow Method ◽

Power Flow Method

This research addresses the problem of the optimal placement and sizing of (PV) sources in medium voltage distribution grids through the application of the recently developed Newton metaheuristic optimization algorithm (NMA). The studied problem is formulated through a mixed-integer nonlinear programming model where the binary variables regard the installation of a PV source in a particular node, and the continuous variables are associated with power generations as well as the voltage magnitudes and angles, among others. To improve the performance of the NMA, we propose the implementation of a discrete–continuous codification where the discrete component deals with the location problem and the continuous component works with the sizing problem of the PV sources. The main advantage of the NMA is that it works based on the first and second derivatives of the fitness function considering an evolution formula that contains its current solution (xit) and the best current solution (xbest), where the former one allows location exploitation and the latter allows the global exploration of the solution space. To evaluate the fitness function and its derivatives, the successive approximation power flow method was implemented, which became the proposed solution strategy in a master–slave optimizer, where the master stage is governed by the NMA and the slave stage corresponds to the power flow method. Numerical results in the IEEE 34- and IEEE 85-bus systems show the effectiveness of the proposed optimization approach to minimize the total annual operative costs of the network when compared to the classical Chu and Beasley genetic algorithm and the MINLP solvers available in the general algebraic modeling system with reductions of 26.89% and 27.60% for each test feeder with respect to the benchmark cases.

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